From mboxrd@z Thu Jan 1 00:00:00 1970 From: "J. Bruce Fields" Subject: Re: PROBLEM: 2.6.35.7 to 3.0 Inotify events missing Date: Sun, 21 Aug 2011 13:07:14 -0400 Message-ID: <20110821170714.GB9296@fieldses.org> References: <20101018223540.GA20730@gradator.net> <20110819230344.GA24784@gradator.net> <20110819233756.GI11512@jl-vm1.vm.bytemark.co.uk> <20110820012943.GD2203@ZenIV.linux.org.uk> <20110820030335.GA14899@jl-vm1.vm.bytemark.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Al Viro , Sylvain Rochet , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jamie Lokier Return-path: Content-Disposition: inline In-Reply-To: <20110820030335.GA14899-DqlFc3psUjeg7Qil/0GVWOc42C6kRsbE@public.gmane.org> Sender: linux-nfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-fsdevel.vger.kernel.org On Sat, Aug 20, 2011 at 04:03:35AM +0100, Jamie Lokier wrote: > Well you still have your sense of humour... > > I've never understood why you think it's about the file manager / > desktop, or why you so strongly dislike the feature. It originated > there historically, but that is not it's primary use. > > The implementation, sure, but you seem to dislike the very *principle* > of subscribing to changes. > > Every interesting use of inotify that I've seen is for some kind of > cache support, to eliminate the majority of stat() calls, to remove > disk I/O (no stat means no inode), to ensure correctness (st_mtime is > coarse and unreliable), It seems rather fragile as an mtime replacement unless it's also got some sort of logging built in at a pretty low level so that you don't lose events while you're not listening. And of course events have to be defined very carefully to avoid problems such as this one. > and to avoid having to modify every > application which might affect any file from which cached items are > derived to explicitly notify all the applications which might use any > of those files. > > You like high performance, reliable and correct behaviour, and high > scalability. So I have never understood why you dislike the > change-subscription principle so strongly, because it is a natural > ally to those properties. I don't think we've seen a design that does all of that yet. --b. -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html